How important is safe_mod in php 5.3?

Hello,
actually safe mod is enabled by default.
But some users need safe_mod disabled, that is not possible with fastcgi for each users,?!
In php 5.3 is safe_mod deprecated, but configurable.
My question is, can safe mod a security problem if it's disabled on php 5.3?

I haven't been using the safe_mod function since years ago , If your kernel is patched and users are in jail and also PHP/Apache is hardened there wouldn't be any security issue because safe_mod is disabled on your PHP .